In general, Customizer allows copying and entire set of panels from one user/company to another.  When I try to copy and individual panel I get this message, "Unable to create the following new library, possibly because it already exists."  However, I do recall being able to copy an INDIVIDUAL panel from one user/company to another but I can't seem to repeat it.  Are only certain panels eligible for individual copying?  Or is there a different procedure to do that?